Incandescent electric lamp.



No. 843,054 PATENTED PEB- 5, 1907. W. R. WHITNEY INGANDESGENT ELECTRIC LAMP.

APPLIOATION FILED 00131, 1904,

Figl.

UNITED STATES;

PATENT OFFICE.

WILLIS WHITNEY, OF SOHENECTADY, NEW YORK, ASSIGNOR GEN- ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

INCANDESCENT ELECTRIC LAMP.

Specification of LttersPatent.

Patented Feb. 5, 1907.

Application filedOct'ober 31, 1904. Serial No. 230.686.

To all whmm Lt flux/y concern:

Be it known that I,.WrLLrs R. Win/river, a

citizen of theUnited States, residing at Schen ectady, in the county of Schenectady and State of New York, have invented certain new and useful Improvements in Incandescent Electric Lamps, of which the following 15 a speclfioation.

My present invention relates more espethe glass envelop. Heretofore it has been the usual practice to employ platinum leading-in conductors. In accordance with 'my invention I provide the glass bulb or envelop with tubes opening intothe interior thereof.

Theopeinends of these tubes I seal into caps of a inetalsuch as copper, iron, or the lik ehaving a higher coefficient of expansion than glass. The filament in the bulb is connected to these caps on one side, whilew-ires or other conductors are connected to the caps on the other or outer sides.

The novel features characteristic of the in vention are pointed out with particularity in the appended claims. The inventionitself, however, will be better understood by reference to the following description, taken in connection with the accompanying drawings, in which- Figure 1 represents one embodiment of my invention and Fig. 2 a modification.

In the drawings the bulb 1 of an incan-.

descent lamp of the usual shape is provided with thereentrant tubular member 2. Ordinarily the upper end of this; tube 2 is pressed while hot around the .platinum leading-in wires, and thus forms a tight seal therewith. In the present case the upper endof the tube 2 is provided with separate tubular extensions 3 and l, rojecting in this case one to the right and the other to the left. The open ends of these small tubes I close hermetically in the following manner:v Over each Iplace a cap, as at 5 and 6, of copper, iron, or other i The tightness of the joint is probably assisted by some combination'between the oxidizedsurfaces of the metal and the parts of the glass in contact therewith. The metal should be sufficiently thin so that it will stretch and will. thus not. exert such a pres sure upon the glass as to shearor'break the same. A thickness of metal of one' one-hundredth of an inch or less I have. found to be satisfactory.

have its ends joined by the usual cement, either directly to. the caps 5 and 6 or, if desired, to wires 8 and 9, which are in turn joined to the caps or integral with the same.

The interior portions of the caps5 and 6' are joined to wires 10 and 11, by which connections are made respectively to the usual screw-threaded shell 12 and contact plug 13. The connections between the wires 10 and 11 J and the caps-5 and 6 may be made by electric welding or by other suitable means and preferably before the caps have been sealed in lace. The wires on either'side of a'cap may, o'wever, be formed integrally therewith.

Inste'ad-ofhaving the tubular extensions 3 and 4 project in opposite directions, as shown in Fig, 2, I may of course arrange them paral lel to-each other, or nearly paralleh'as shown in Fig.2, in which the glass tubes 14 and 15, with their respective'caps 16. and17, correspond to the tubes 3 and 4' inFi 1'. other respects the lamp shown irfiig 2 is the sameras that'shown in Fig. 1, and -therefore requires no furtherdescription' as to details.

1 am aware that myinvention maybe embodied in other forms than that shown, and for this reason it will beunderstoodthat the representations in the drawin sare merely illustrative of m invention. therefore do not wish to be imited to" the exact details shown and described.

What I claim as new, and desire to secure by Letters Patent of the United States, .lF

1. The combination of a lamp-bulb having a rentran't tubular portion, tubular exten sions thereof terminating within the larnp- 'bulb,me'tal ca s having a coefficient of ex ansion greater t an that of the material 0 the lamp-bulb and tightly clas 9mg the ends of these tubular extensions an in intimate con tact with the glass, and electrical connections on; either side ofeach of said caps- The carbon filament ,7- of the lamp may "35 In all 2. The combination of alampbulb having aren'tran't portion, small tubular extensions l than that of the material of the bulb and of said rentrant portion, and seals for said tightly clasping the end of the tube, and a tubular extensions each consisting of a cap of fil:1 1nent electrically connected. to said metal metalhavin acoefiicientof expansion greater caps.

than thato the material of the lamp-hull) 1 in Witness whereof I have hereunto set my and tilgiltly elsisping the ienc% of thle) tfibp. hand this 29th day of October, 1904.

3. ecom ination o a am u o iaving' ,i r -H I 1 y a re'ntrant portion, small tubul arextension ILLlb HUAPA of said rentrant portion, seals for said tubular extensions, each consisting of a cap of metal having a coefficient of expansion are ater Witnesses BENJAMIN B. HULL, HELEN Ontronn. 

